Aerosol plastic container made from an isosorbide containing copolyester and aerosol dispenser comprising said aerosol plastic container

ABSTRACT

The invention relates to a plastic preform suitable to be stretch blow molded in order to form an aerosol container ( 20 ) or to an injection stretch blow molded aerosol container ( 20 ), wherein the preform or container are made of a polymeric material that comprises a copolyester including at least 1 mole % of isosorbide as comonomer and having an intrinsic viscosity of at least 0.7 dL/g.

TECHNICAL FIELD

The present invention relates to a novel injection stretch blow moldedaerosol container and to a novel plastic preform suitable to be stretchblow molded in order to form an aerosol container. The invention alsorelates to a novel aerosol plastic dispenser for dispensing an aerosolor other comparably pressurized product.

PRIOR ART

Aerosol dispensers are well known in the art. More especially, aerosoldispensers comprise an aerosol container that contains an aerosol (orother comparably pressurized product), and that is fitted with a valvedispensing device for dispensing the aerosol. Aerosol dispenserscomprising an aerosol container made of plastic are for exampledisclosed in US patent application US 2004/0149781 and in PCTapplication WO 2007/140407.

The term “aerosol” used herein encompasses both aerosol, literally, andalso other liquids or flowable products that can be dispensed frompressurized containers in a manner comparable to aerolized products.Such other liquids or flowable products include but are not limited tofoam or gel preparations or to liquid products delivered frompressurized containers but not necessarily in a pulverized form.

Examples of typical aerosol compositions can be notably but notexhaustively insecticides, insect repellents, hairsprays, cosmeticsprays, air fresheners, cleaning preparation, shave preparationsincluding foams and gels.

When a plastic container is used for making an aerosol container, thehigh internal pressure inside the plastic container can detrimentallylead to mechanical deformations of the plastic aerosol container, andeven worth to the burst of the aerosol plastic container. This problemof mechanical deformations and burst of the aerosol plastic containerunder the effect of high internal pressure is even more critical whenthe container has an aesthetic and ergonomic shape with a concavesidewall gripping portion, as the one depicted for example on FIG. 1 or2 of US patent application US 2004/0149781 or for example on FIGS. 1, 5,6B, 6C, 7A to 7F, 8A, 8D, 8E, 8G, 8H of PCT application WO 2007/140407.Said concave sidewall gripping portion is actually more sensible tomechanical deformation under high internal pressure compared with acontainer having a cylindrical body with a straight sidewall or with aconvex sidewall.

This is the reason why an aerosol plastic container has to bepressure-resistant in order to withstand high internal pressure. Moreparticularly, to date in the European community, plastic aerosoldispensers have to fulfill the technical requirements of standard FEA621 of March 2007 meeting the provisions of the Aerosol DispensersDirective 75/324/EEC of May 1975 and related to the measurement ofinternal pressure resistance of empty containers without valves.

PET (Polyethylene Terephthalate) is a well-known polyester that iswidely used for making biaxially stretched containers, and moreparticularly Injection Stretched Blow Molded (ISBM) containers. ISBMgrade PET has typically an Intrinsic Viscosity (IV) between 0.7 dL/g and0.8 dL/g and a glass transition temperature (Tg) of about 75° C. to 80°C.

Typically, polyesters, like for example PET homo or copolymers, canadvantageously exhibit strain-induced crystallization upon substantialorientation, in a region above the Natural Stretch Ratio (NSR) of thepolymer. It is well-known that for obtaining ISBM polyester containershaving good mechanical properties, the biaxial stretching of thepolyester must be sufficiently important to be in the strain-hardeningregion of the polyester, slightly beyond the NSR of the polymer.

The NSR of a polymer can be knowingly determined in a free-blowingexperiment. Free-blowing of thermoplastics, in particular PET and PETcopolymers, is a well known technique used to obtain empirical data onthe stretching behavior of a particular resin formulation. The method offree blowing PET preforms is described in “Blow Molding Handbook”,edited by Donald V. Rosato, Dominick V. Rosato, Munich 1989. Theterm“free-blowing” means that a preform is blow-molded without using amold. Free-blowing a bottle from a preform involves heating the preformto a temperature above its glass transition temperature and thenexpanding the preform outside of a mold so that it is free to expandwithout restriction until the onset of strain hardening. Strainhardening can be detected in a stress-strain curve as an upswing instress following the flow plateau. To a large extent the strainhardening is associated with molecular ordering processes in the resin.If the blow pressure and heating of the preform is properly set for agiven preform, it will continue to expand until all of the PET isoriented to the point that stretching will stop at about the naturalstretch ratio, or slightly beyond.

Standard ISBM grade PET, even in the strain-hardening region, is howevergenerally not suitable for making pressure-resistant ISBM aerosolcontainers that withstand high internal pressure, and more generally formaking pressure-resistant ISBM aerosol containers that would fulfill thetechnical requirements of standard FEA 621 of March 2007.

The diol 1,4:3,6-dianhydro-D-sorbitol, referred to hereinafter asisosorbide, the structure of which is illustrated below, is readily madefrom renewable resources, such as sugars and starches, in particularnatural starch extracted from maize, wheat, potatoes and peas. Forexample, isosorbide can be made from D-glucose by hydrogenation followedby acid-catalyzed dehydration.

Isosorbide has been already used as a monomer for incorporation intopolyesters such as PET at low levels. The incorporation of isosorbide ascomonomer in a copolyester knowingly reduces the intrinsic viscosity ofthe copolyester.

Isosorbide containing copolyesters, and in particular PolyethyleneTerephthalate containing Isosorbide (PEIT) polymers, as well as theirprocess of manufacturing by melt polymerization or by solventpolymerization are thus well-known in the art.

Isosorbide containing copolyesters, and in particular PolyethyleneTerephthalate containing Isosorbide (PEIT) polymers, are used to date inmany applications, and for example for making films or containers. Inparticular, Polyethylene Terephthalate containing Isosorbide (PEIT) canbe used for making hot-fillable containers that withstand hightemperatures.

As clearly identified in the following publication, the incorporation ofisosorbide as comonomer in a copolyester increases the glass transitiontemperature (Tg) of the copolyester (see FIG. 2—Variation of Tg versusmol % of Isosorbide), and has also an impact on the strain hardeningcharacteristics of the polymer: “Properties and Strain HardeningCharacter of Polyethylene Terephthalate Containing Isosorbide”, RameshM. Gohil, Polymers Engineering and Science—2009 pages 544-553.

Although Isosorbide containing copolyesters, and in particularPolyethylene Terephthalate containing Isosorbide (PEIT) polymers can beused to date in many applications, one cannot find on the market ISBMaerosol containers made form a isosorbide containing copolyesters and inparticular made from a PEIT polymer.

There is consequently an unsatisfied need to propose ISBMpressure-resistant aerosol containers made from an isosorbide containingcopolyester and in particular made from a PEIT polymer.

OBJECTIVE OF THE INVENTION

A main objective of the invention is thus to propose a novelpressure-resistant aerosol plastic container made from an isosorbidecontaining copolyester, and in particular (but not only) made from aPEIT polymer.

SUMMARY OF THE INVENTION

A first object of the invention is a plastic preform adapted to bestretch blow molded in order to form an aerosol container or aninjection stretch blow molded aerosol container, said preform or aerosolcontainer being made from a polymeric material that comprises acopolyester including at least 1 mole % of isosorbide as comonomer andhaving an intrinsic viscosity of at least 0.7 dL/g.

The ISBM aerosol container of the invention exhibit very good mechanicalproperties, and in particular can advantageously withstand high internalpressure.

Aerosol containers are generally containers of small volumes, typicallynot more than 750 ml. Consequently, when aerosol containers are made byusing ISBM technology, only low stretch ratios can be practiced.

The incorporation of isosorbide as comonomer in a copolyester has astrong impact on the onset of the strain-hardening region of thecopolyester, and more particularly increases the NSR of the copolyester.Otherwise stated, isosorbide containing copolyesters, and in particularPolyethylene Terephthalate containing Isosorbide (PEIT) polymers,require a much higher elongation for reaching the strain-hardeningregion than a standard PET homopolymer.

As a result, prior to the invention, it was generally considered thatthe use of isosorbide containing copolyesters, especially with highlevel of isosorbide, would eventually improve the thermal properties ofthe container because a higher Tg would achieved, but would not besuitable for making pressure-resistant aerosol ISBM containers havingthe required mechanical properties to withstand the typical highinternal pressure, especially for making pressure-resistant aerosol ISBMcontainers of small volume with low stretch ratios, because the NSR ofthe copolyester would be too high.

The invention removed this prejudice by increasing the intrinsicviscosity of the isosorbide containing copolyester, for example bycarrying out a Solid State Polymerization (SSP) of the copolyester for aperiod sufficient to achieve an IV of at least 0.7 dL/g. This increaseof IV advantageously decreases the NSR of the copolyester and enables toobtain a copolyester combining a high level of isosorbide and a lowerNSR and suitable for making pressure-resistant ISBM aerosol containers.

More particularly, the preform or ISBM aerosol container of theinvention can have any one of the following optional characteristics:

-   -   The preform or container is essentially made from a copolyester        including at least 1 mole % of isosorbide as comonomer and        having an intrinsic viscosity of at least about 0.7 dL/g.    -   The copolyester is Polyethylene Terephthalate containing        Isosorbide (PEIT).    -   The copolyester includes at least 3 mole (%) of isosorbide as        comonomer, and more particularly at least 5 mole (%) of        isosorbide as comonomer.    -   The copolyester includes not more than 15 mole (%) of isosorbide        as comonomer, and preferably not more than 8 mole (%) of        isosorbide as comonomer.    -   The intrinsic viscosity of the copolyester is at least 0.8.dL/g,        more particularly at least. 0.9.dL/g.    -   The intrinsic viscosity of the copolyester is not more than        2.dL/g.    -   The injection stretch blow molded aerosol container has an axial        stretch ratio (S_(a)) of not more than 3, and preferably of not        more than 2.55.    -   The injection stretch blow molded aerosol container has a radial        stretch ratio (S_(r)) of not more than 2.5, and preferably of        not more than 2.4.    -   The injection stretch blow molded aerosol container has an        overall stretch ratio (S) of not more than 9, and preferably of        not more than 7.    -   The injection stretch blow molded plastic container has a        concave sidewall gripping portion.    -   The injection stretch blow molded plastic container has a volume        of not more than 750 ml, and preferably of not more than 500 ml.

The invention also relates to an aerosol dispenser comprising theaforesaid injection stretch blow molded aerosol container and a valvedispensing device suitable for dispensing an aerosol contained in theaerosol container.

BRIEF DESCRIPTION OF THE DRAWINGS

Other technical characteristics and advantages of the invention willappear more clearly on reading the following detailed description whichis made by way of non-exhaustive and non-limiting example, and withreference to the appended drawings, as follows:

FIG. 1 is a longitudinal cross-section view of preform suitable to bestretch blow molded in order to form a pressure-resistant aerosolplastic container.

FIG. 2 is a longitudinal cross-section view of an aerosol dispensercomprising an ISBM aerosol container that has been obtained by biaxiallystretch blow molding the preform of FIG. 1, and that is fitted with avalve dispensing device suitable for dispensing an aerosol contained inthe aerosol container.

DETAILED DESCRIPTION

In reference to FIG. 2, the aerosol dispenser 2 comprises a pressureresistant aerosol container 20 which is knowingly hermetically closed bya valve dispensing device 21. Said valve dispensing device 21 comprisesa closure 210 that is covering the top opening 200 of the aerosolcontainer 20, and that is sealingly attached to the neck 201 of theaerosol container 20. Said closure 210 includes a valve member 211having an axially extending valve stem 212 which can be either depressedor tilted to release the aerosol contained within the container 20. Thestructure and functioning of the valve dispensing device 21 are wellknown in the art and will not be described in details. One skilled inthe art can besides refer to the disclosure of US 2004/0149781.

Pursuant to the invention, the pressure resistant plastic aerosolcontainer 20 is an injection stretch blow molded container.

FIG. 1 shows a plastic preform 1 suitable to be stretch blow molded inorder to form a pressure-resistant aerosol plastic container

This preform 1 is made of a substantially tubular body of axial lengthL₁, which is closed at its bottom end and has a pouring opening at itsupper end. More especially, said preform 1 comprises a neck portion 10terminated by a pouring opening 100, a so-called gate portion 12 forminga closed bottom end, and a body portion 11 that is extending betweensaid gate portion 12 and said neck portion 10. The neck portion 10comprises a protruding neck support ring 101 of bigger diameter. Thebody portion 11 comprises a main cylindrical portion 110 ofsubstantially constant wall thickness WT and an upper transition portion111. The inner face of the main portion 110 can be also conical.

In this particular example of FIG. 1, the gate portion 12 is made of aconvex portion having substantially a hemi-spherical shape, andterminated by a small central protruding injection point 20. The size ofthis injection point 20 corresponds to the size of the output orifice ofthe hot runner nozzle that is being used for injecting the plasticmaterial in the mould. The shape of the gate portion 12 is notnecessarily hemi-spherical, but the gate portion 12 can have any othershape, and in particular can be for example conical.

When this preform 1 is biaxially stretch blow molded in a mould, theneck portion 10 is used for maintaining the preform in the blowingmould, and is thus not stretched. The body portion 11 is biaxiallystretched (in a longitudinal direction X and in a radial direction Y) inorder to form a container body of higher volume. The gate portion 12 isalso biaxially stretched in order to form typically the bottom base ofthe injection stretch blow molded container.

Within the scope of the invention a “one stage process” or a “two stagesprocess” can be used. In the one stage process”, the stretch-blowmoulding step of the preform is performed in line immediately after thefirst injection step (preform injection). In the “two stages process”,the stretch-blow moulding step of the preform is postponed, and areheating of the preform is performed prior to this stretch-blow moldingstep.

The final shape and size of the container will depend of the blow moldthat is being used and of the stretch ratios that are practiced. Forexample but not only, the preform 1 can thus be stretch blow molded inorder to make the pressure-resistant aerosol container 20 of FIG. 2.

The invention is however not limited to the particular shape ordimensions of the aerosol container 20 of FIG. 2.

In particular, the base 202 (FIG. 2) of the aerosol container 20 is notnecessarily spherical like the container depicted on FIG. 2, but can beof any shape. More especially, the base 202 of the aerosol container 20can also be a base including an inwardly-oriented central dome, alsocommonly called “champagne” base, or can be a “petaloid” base like forexample the base of the container of FIG. 8D of WO 2007/140407.

In the particular aerosol container 20 of FIG. 2, the sidewall of thecontainer comprises a main central portion 203 which is concave andforms a kind of hyperboloid configuration, which provides a veryergonomic structure that can be easily handled by a user. In othervariants, the sidewall of the container 2 can have any other shape,including straight wall portion, convex wall portions, etc. . . .

Pursuant to the invention, in order to obtain a pressure-resistantinjection stretch blow molded aerosol container 20 that can withstandhigh internal pressure, the polymeric material used for making thepreform 1 or container 2 is a copolyester including at least 1 mole % ofisosorbide as comonomer and having an intrinsic viscosity of at least0.7 dL/g, more preferably of at least 0.8 dL/g, and even more preferablyof at least 0.9 dL/g.

For achieving said required minimum IV of at least 0.7 dL/g. theintrinsic viscosity of the Isosorbide containing copolyester hasgenerally to be increased for example by carrying out a Solid StatePolymerization (SSP) of the copolyester for a period sufficient toachieve the required minimum IV. This increase of IV enablesadvantageously to lower the NSR of the isosorbide containing polyesterand to at least partially compensate the increase of the NSR caused bythe incorporation of isosorbide in the copolyester. The required IVlevel can however also be obtained directly, i.e. without a SSPpost-treatment, by carrying out a suitable polymerization process.

More preferably, the isosorbide containing polyester comprises acopolyester that includes at least 5 mole % of isosorbide as comonomer.

More particularly, the isosorbide containing polyester comprises acopolyester that includes not more than 15 mole % of isosorbide ascomonomer, and even more preferably not more than 8 mole % of isosorbideas comonomer.

The isosorbide containing copolyester may be formed by any method knownin the art. Preferably, however, the polyester is formed by solvent ormelt polymerization.

Preferably, the isosorbide containing copolyester is PolyethyleneTerephtalate containing Isosorbide (PEIT), although other polyesters arealso suitable for practicing the invention.

Preferably, the isosorbide containing copolyester comprisesterephthaloyl moieties; optionally, one or more other aromatic diacidmoieties; ethylene glycol moieties; isosorbide moieties; and, optionallyone or more other diol moieties.

More particularly, said terephthaloyl moieties can be derived fromterephthalic acid or dimethyl terephthalate.

More particularly the isosorbide containing copolyester can furthercomprise diethylene glycol moieties

Aforesaid one or more other diol moieties can be derived from aliphaticalkylene glycols or branched aliphatic glycols having from 3-12 carbonatoms and having the empirical formula HO-CnH2n-OH, where n is aninteger from 3-12; including branched diols such as2,2-dimethyl-1,3-propanediol; cis or trans-1,4-cyclohexanedimethanol andmixtures of the cis and trans isomers; triethylene glycol;2,2-bis[4-(2-hydroxyethoxy)phenyl]propane;1,1-bis[4(2-hydroxyethoxy)phenyl]cyclohexane;9,9-bis[4-(2hydroxyethoxy)phenyl]fluorene;1,4:1,4:3,6-dianhydromannitol; 1,4:1,4:3,6-dianhydroiditol; and1,4-anhydroerythritol.

Preferably, but optionally, the number of terephthaloyl moieties in thepolymer is in the range of about 25% to about 75 mole % (mole % of thetotal polymer).

In a preferred embodiment, ethylene glycol monomer units are present inamounts of about 5 mole % to about 49.75 mole %. The polymer may alsocontain diethylene glycol moieties. Depending on the method ofmanufacture, the amount of diethylene glycol moieties is for example inthe range of about 0.0 mole % to about 25 mole %.

Experiments

Three different batches (Ref. A, Ref. B, Ref. C) of ISBM monolayeraerosol containers having similar shapes and dimensions, and moreespecially having a sidewall hyperboloid configuration similar to thecontainer of FIG. 2, have been manufactured with three differentpolymeric compositions, by injecting preforms 1 having a weight of 35 gand by biaxially stretch blow molding said preforms into ISBM aerosolcontainers having a volume of 335 ml. The wall thickness (WT) of themain cylindrical body portion 11 of the preform 1 was about 4.5 mm(+/−5%).

The mold blowing step was performed with an axial stretch ratio S_(a)around 2.4 mm.

This axial stretch ratio (S_(a)) is knowingly defined in a standard wayby formula:

$S_{a} = \frac{L}{}$

wherein: L is the container developed length (FIG. 2) and l is thepreform neutral fibre developed length (FIG. 1).

The radial stretch ratio (S_(r)) was around 2.55 mm. This radial stretchratio (S_(r)) is knowingly defined in a standard way by formula:

$S_{r} = \frac{D}{d}$

wherein D is the maximum container outside diameter (see FIG. 2) and dis the maximum preform outside diameter Dp (FIG. 1) minus the wallthickness WT (d=Dp−WT).

The overall stretch ratio (S) of the aerosol containers was around 6.This Overall stretch ratio (S) is knowingly defined in a standard way byformula:

S=S _(a) ×S _(r)

The first batch (Ref. A) of ISBM aerosol containers was made fromPolyethylene Terephthalate containing Isosorbide (PEIT) [i.e.Poly(etyhylene-co-isosorbide)terephthalate]. More particularly, saidPEIT was containing 5.8 mole % of Isosorbide (5.8 mole % PEIT). This 5.8mole % PEIT was obtained in a known way by melt polymerization. This 5.8mole % PEIT issued from the melt polymerization was subjected to a SSPduring a period of time sufficient to raise the IV of the Isosorbidecontaining copolyester up to about 0.95 dL/g.

The second batch (Ref B) of ISBM aerosol containers was made from a PETresin of standard grade having an intrinsic viscosity of about 0.86dL/g.

The third batch (Ref;C) of ISBM aerosol containers was made from a PETresin having an intrinsic viscosity of about 0.95 dL/g. Said PET resinwas a copolymer PET commercialized by Artenius Tech Polymers undercommercial reference “Artenius HOT”.

For all the three batches A, B and C, the intrinsic viscosity (IV) ofthe resin before injection was measured pursuant to following methodbased on the ISO 1628 standard:

-   10 g of material is dried for 3 h under vacuum at 120° C.-   10 g of material is grinded to a mesh size of 0.5 mm-   0.50 g of grinded material is weighed into a volumetric flask of 100    ml.-   Solvent is added to dissolve the sample. The solvent is DCA    (dichloroacetic acid).-   The volumetric flask is heated and stirred until everything is    dissolved.-   The solution is stabilized at 25° C. and filled with solvent until a    volume of exact 100 ml.-   The solution is measured in a dedicated capillary viscometer and the    IV is calculated according to the ISO 1628 standard, taking in to    account the solvent that is used.

The intrinsic viscosity (IV) of the preforms of the three batches wasalso measured by carrying out the aforesaid method with m-cresol assolvent. The results showed an IV drop due to a degradation of thepolymer during the injection process. The IV of the preforms of thefirst batch (Ref. A) was around 0.8 dL/g. The IV of the preforms of thesecond batch (Ref. B) was around 0.73 dL/g. The IV of the preforms ofthe third batch (Ref. C) was around 0.78 dL/g.

For all the three batches A, B and C, the glass transition temperature(Tg) of the resins, was knowingly measured by Differential Scanningcalorimetry (DSC) with an equipment DSC 821e from Mettler Toledo. The Tgof the 5.8 mole % PEIT (Ref. A) was around 89.6° C. The Tg of the PETresin of the second batch (Ref. B) was around 79.6C. The Tg of the PETresin of the third batch (Ref. C) was around t 79.5° C.

The following mechanical and thermal tests have been carried out on thethree batches A, B and C of aerosol containers.

Hydraulic Test.

The goal of this test is to evaluate the container dimensions stabilityafter pressurizing the aerosol container. Test pressure needs to be 50%higher than the internal pressure in the container at 50° C.

-   Calculation for the pressure (P) used for the hydraulic test: The    pressure at 50° C. is defined, using the perfect gas low.-   We take the assumption that we have no creep on the container, this    means that the volume (V) at 20° C. is the same as the volume ‘(V)    at 50° C. (which is more severe than reality).

Perfect gas low=>P.V=k·T (k=constant)

-   If V is constant, then:    P_((20° C.))/T_((20° C.))=P_((50° C.))/T_((50° C.))-   Pressure=Absolue pressure-   T°=Absolu T° (° K)

P _((50° C.)) =P _((20° C.)) ·T _((50° C.)) /T _((20° C.))=>8 bar(abs)·323° K/293° K=8.82 bar (abs)=>7.82 bar (relative)

-   Conclusion 7 bar at 20° C. give a pressure of 7.82 bar at 50° C.    (considering no volume expansion)-   For the hydraulic test, he the internal pressure in the container at    50° C. is thus 7.82 bar.

Hydraulic pressure=Pressure at 50° C.+50%=>7.82+50%=11.73 bar=>Testpressure=12 bar

The test is then performed as follows:

-   Take 10 containers ad random    -   Measure the container at the start: height, diameter        shoulder-label-base area, base clearance, overflow volume.    -   Pressurize the container for 25 sec at 12 bar (=calculated        pressure of container at 50° C.+50%) using the SOMEX Delta 3000        PET bottle Pressure Tester.    -   Re-measure the container on an identical way as measured at the        start    -   Evaluate the container visually. A slight symmetrical distortion        shall be allowed provided that the container passes the burst        test.

Material Resistance to Temperature—Drop Test

The goal of this test is to evaluate the container when it is droppedfrom a height of 1.8 m to a concrete floor and this at differenttemperatures. Ensure that the orientation, of the test container at dropis statistically random, but that direct impact on the valve or valveclosure is avoided. Aerosol containers must be designed that it shallnot break or leak.

-   -   Aerosol containers needs to be tested at 3 different temperature        conditions:        -   −18° C. for at least 24h        -   room temperature 20-22° C. for at least 1 h        -   55° C. for at least 6 h (dry air)    -   Take at random 25 aerosol container for each group of        temperature testing    -   Filling of the container 85% of the overflow volume with water.        For the containers that need to be tested at −18° C. fill the        container with a mixture of 50/50 water/antifreeze    -   Closing of the container with metal crimp valve    -   Pressurize the container with compressed air at 8.0 bar        relative. (this is the calculated pressure @50° C.)    -   Condition the 25 containers for the defined time at the 3        different temperatures.    -   Drop the containers random on the concrete floor from a height        of 1.8 m directly after removing them from the climate chamber    -   Evaluate the aerosol containers after drop: no leak or break is        allowed on the 3 different sets of containers.

Burst Test

The goal of this test is to evaluate the ability of an aerosol containerto withstand to a certain internal pressure. Pressure at which thecontainer is bursting needs to be minimum 20% higher than the testpressure. Equipment used for this test is the Delta 3000 PET bottlePressure Tester from SOMEX. Minimum burst pressure calculation: Testpressure of 12 bar (relative)+20%=>14.4 bar (relative)

-   -   Take 10 aerosol containers ad random    -   Container is filled brimful with water, and the initial pressure        on the container is 4 bar for a hold time of 13 sec. After this        the pressure is built up with a ramp of 0.69 bar/sec until the        container bursts.    -   Burst pressure for all the containers needs to be above 14.4        bar.

Material Resistance to Temperature—Hot Air

The goal of this test is to indicate the temperature where thedeformation of the container is induced. Temperature for this test is 7°C. lower than Tg with a max. test temperature of 75° C. and mintemperature of 65° C. It is allowed that the containers deform, butwithout breakage or leakage creating a hazardous environment.

-   -   Take 25 aerosol containers at random    -   Fill the containers with water up to a headspace volume of 15%        of the overflow volume of the container    -   Close the container with metal crimp valve    -   Pressurize the container with compressed air at 8.0 bar        (relative)    -   Condition the 25 containers for the min. 5 H at 75° C. dry air        in the climate cupboard.    -   Evaluate the containers on leakage and breakage when the hot air        test is finished

Top Load

The goal of this test is to evaluate the aerosol containers resistanceto a vertical load before its first deformation. Equipment used for thistest is the INSTRON 3366 Top load tester with a load cell of 5000N. Theresult is the maximum compressive load (in kgf) a container canwithstand before it loses 1% of the compressive load applied. Test isdone with a speed of 50 mm/min.

-   -   Take at random 10 aerosol containers    -   Test each container separately    -   Note the place of deformation at the end of the test and the max        compressive load (end of test: 1% rate of compressive load)

Accelerated Stress Cracking

The objective of the accelerated stress cracking is to simulate stressexperienced by containers during pressure filling, shipping and storage.

The test is performed as follows:

-   -   Take the containers (normal sample size: 10) at random from the        samples to be tested.    -   Fill each container with carbonated water at the requested        volume of CO₂ and cap it.    -   Pour 0.2% NaOH solution into cut bases.    -   Complete    -   Submerge the base of the bottles in the caustic solution into        the cut bases and start the chronometer    -   Measure the immersion time until the bottle base bursts or leaks        using the chronometer (stop the experiment in case the bottle        does not show any failure after 30 minutes)

The permeation of the aerosol containers of the first batch (Ref. A) hasbeen also measured pursuant to the following permeation test.

Permeation

The goal of this test is to measure the Oxygen transmission rate of theaerosol container. Equipment used to determine the permeation is theMOCON Oxtran 2/20 that uses a Coulometric Sensor (Coulox) to determinethe O2 concentration. Test method used is derived from the ASTM D 3985and the ASTM F 1307. The Aerosol container is mounted on a metal fixtureand flushed with N2 to purge the air out of the bottle. As the outsideof the bottle is in contact with ambient air (20.9% O₂), O₂ permeatestrough the bottle wall and is transported with the N₂ flow to the CouloxSensor.

The test is performed as follows:

-   -   Take 2 aerosol containers ad random    -   Glue the containers on the metal fixture with the 2 component        glue    -   Condition the bottle for 50 h with N₂    -   Measurement is finished when the O₂ concentration is stable        (less than 1% difference with concentration of 10 h before)    -   Result is given in cc/pack/day—22° C.—atmospheric        pressure—ambient air    -   ppm/day or ppm/year is calculated

Test Results Hydraulic Test

The results of the hydraulic test are summarized in tables IA, IB andIC.

TABLE IA Hydraulic Test- Ref. A: Initial 12 bar Δ Δ total height max(mm) 181.18 181.29 0.12 0.07% shoulder diameter (135.0 mm) (mm) 56.4656.50 0.03 0.06% P/L shoulder diameter (135.0 mm) (mm) 56.77 56.76 −0.01−0.02% 90° label diameter (80.0 mm) P/L (mm) 47.77 47.77 0.00 −0.01%label diameter (80.0 mm) 90° (mm) 47.79 47.82 0.03 0.05% heel diameter(20.0 mm) P/L (mm) 56.92 56.89 −0.03 −0.06% heel diameter (20.0 mm) 90°(mm) 56.62 56.61 −0.01 −0.01% base clearance (mm) 10.45 10.43 −0.02−0.21% overflow volume (ml) 333.92 334.18 0.26 0.08%

TABLE IB Hydraulic Test- Ref. B: Initial 12 bar Δ Δ total height max(mm) 181.11 181.09 −0.02 −0.01% shoulder diameter (135.0 mm) (mm) 56.4456.42 −0.02 −0.04% P/L shoulder diameter (135.0 mm) (mm) 56.55 56.50−0.05 −0.09% 90° label diameter (80.0 mm) P/L (mm) 47.88 47.87 −0.01−0.02% label diameter (80.0 mm) 90° (mm) 47.55 47.52 −0.02 −0.05% heeldiameter (20.0 mm) P/L (mm) 57.04 56.96 −0.08 −0.13% heel diameter (20.0mm) 90° (mm) 56.63 56.60 −0.03 −0.05% base clearance (mm) 10.19 10.190.00 0.00% overflow volume (ml) 332.48 332.35 −0.14 −0.04%

TABLE IC Hydraulic Test- Ref. C: Initial 12 bar Δ Δ total height max(mm) 181.13 181.07 −0.06 −0.03% shoulder diameter (135.0 mm) (mm) 56.5556.53 −0.02 −0.04% P/L shoulder diameter (135.0 mm) (mm) 56.53 56.560.03 0.05% 90° label diameter (80.0 mm) P/L (mm) 47.97 47.90 −0.07−0.14% label diameter (80.0 mm) 90° (mm) 47.40 47.41 0.01 0.02% heeldiameter (20.0 mm) P/L (mm) 57.03 57.05 0.02 0.04% heel diameter (20.0mm) 90° (mm) 56.49 56.51 0.03 0.04% base clearance (mm) 10.04 10.03 0.00−0.03% overflow volume (ml) 332.70 332.76 0.07 0.02%

The results are similar for the aerosol containers of the three batchesA, B and C that all successfully passed the hydraulic test.

Material Resistance to Temperature—Drop Test

All the aerosol containers of the first batch (Ref A) successfullypassed the drop test for the three temperatures conditions i.e.:

-   -   −18° C. for at least 24 H    -   room temperature 20-22° C. for at least 1 h    -   55° C. for at least 6 h (dry air)

Burst Test

All the aerosol containers of the three batches (Ref A, B and C)successfully passed the burst test (Burst pressure for all the aerosolcontainers was above 14.4 bar).

Material Resistance to Temperature—Hot air

All the aerosol containers of the first batch (Ref A) successfullypassed the test. The aerosol containers of the first batch (Ref. A) didnot exhibit any leakage after 5 h at 75° C.

In return, the aerosol containers of the second batch (Ref B) and thirdbatch (Ref. C) did not successfully passed the test, and were leakingafter 5 h at 75° C.

Top Load

The results of the hydraulic test are summarized in tables IIA, IIB andIIC.

TABLE IIA To load Test- Ref. A: Standard Average Deviation Min Max Force(Kg) 70.7 4.96 66.0 80.0 Location of failure Finish pushed into theshoulder

TABLE IIB To load Test- Ref. B: Standard Average Deviation Min Max Force(Kg) 74.8 1.05 73.1 76.3 Location of failure Finish pushed into theshoulder

TABLE IIC To load Test- Ref. C: Standard Average Deviation Min Max Force(Kg) 83.4 3.22 77.6 88.4 Location of failure Finish pushed into theshoulder or deformation of the body

Stress Cracking

All the aerosol containers of the three batches A, B and C successfullypassed the stress cracking test. No burst and no crack appears after 30minutes.

Permeation

The result of the permeation of the aerosol containers of the firstbatch (Ref. A) are summarized in table III.

TABLE III Permeation- Ref A. Brimfull volume (ml) 333.82 (cm³/day)0.026832 ppm(day) 0.11 ppm/year 41.94

The invention is not limited to an injection stretch blow molded aerosolcontainer made from a copolyester including at least 1 mole % ofisosorbide as comonomer and having an intrinsic viscosity of at leastabout 0.7 dL/g. The invention can be also practiced with a polymer blendcomprising said copolyester including at least 1 mole % of isosorbide ascomonomer and having an intrinsic viscosity of at least about 0.7 dL/gand another polymer, in particular another polyester.

What is claimed is: 1.-15. (canceled)
 16. A plastic preform adapted tobe stretch blow molded to form an injection stretch blow moldedcontainer, the preform comprising: a polymeric material that comprises acopolyester including at least 1 mole % of isosorbide as comonomer andhaving an intrinsic viscosity of at least 0.7 dL/g.
 17. The preform ofclaim 16, wherein the preform is comprised of copolyester including atleast 1 mole % of isosorbide as comonomer and having an intrinsicviscosity of at least about 0.7 dL/g.
 18. The preform of claim 16,wherein the copolyester is polyethylene terephthalate containingIsosorbide (PEIT).
 19. The preform of claim 16, wherein the copolyesterincludes at least 3 mole % of isosorbide as comonomer.
 20. The preformof claim 16, wherein the copolyester includes at least 5 mole % ofisosorbide as comonomer.
 21. The preform of claim 16, wherein thecopolyester includes not more than 15 mole % of isosorbide as comonomer.22. The preform of claim 16, wherein the copolyester includes not morethan 8 mole % of isosorbide as comonomer.
 23. The preform of claim 16,wherein the intrinsic viscosity of the copolyester is at least 0.8.dL/g.24. The preform of claim 16, wherein the intrinsic viscosity of thecopolyester is at least 0.9.dL/g.
 25. The preform of claim 16, whereinthe intrinsic viscosity of the copolyester is not more than 2.dL/g. 26.An injection stretch blow molded container, the container comprising: apolymeric material that comprises a copolyester including at least 1mole % of isosorbide as comonomer and having an intrinsic viscosity ofat least 0.7 dL/g.
 27. The injection stretch blow molded container ofclaim 26, wherein the container has an axial stretch ratio (S_(a)) ofnot more than
 3. 28. The injection stretch blow molded container ofclaim 26, wherein the container has an axial stretch ratio (S_(a)) ofnot more than 2.55.
 29. The injection stretch blow molded container ofclaim 26, wherein the container has a radial stretch ratio (S_(r)) ofnot more than 2.5.
 30. The injection stretch blow molded container ofclaim 26, wherein the container has a radial stretch ratio (S_(r)) ofnot more than 2.4.
 31. The injection stretch blow molded container ofclaim 26, wherein the container has an overall stretch ratio (S) of notmore than
 9. 32. The injection stretch blow molded container of claim26, wherein the container has an overall stretch ratio (S) of not morethan
 7. 33. The injection stretch blow molded plastic container of claim26, wherein the container includes a concave sidewall gripping portion.34. The injection stretch blow molded plastic container of claim 26,wherein the container has a volume of not more than 750 ml.
 35. Theinjection stretch blow molded plastic container of claim 26, wherein thecontainer has a volume of not more than 500 ml.
 36. An aerosol dispensercomprising the injection stretch blow molded aerosol container of claim26, including a valve dispensing device configured to dispense aerosolcontents from the container.